Bowsing a floatable unit such as a liferaft to a vessel or to an offshore installation is a difficult task. There are many different circumstances which make it difficult to position a floatable unit and maintain its position.
These circumstances may inter alia be Stokes drift, wave heights, wind load, rolling of the vessel and drift of the vessel.
In addition, the capacity of the evacuation systems in relation to persons to be evacuated tends to increase. Thus, the number of liferafts, as well as their size, increases. Accordingly, higher impact and forces may be exerted on the bowsing systems.
Since the forces and loads exerted on the bowsing today are considerable and will be even higher in the future, especially in high seas and under heavy weather conditions, it is difficult to control the bowsing of the known systems. Also, if the vessel and the liferafts are moving at different speeds, the bowsing system shall be configured to control the liferafts independently and together. However, during this control of the liferafts, a certain “braking distance” is necessary, otherwise the inertia of the system will peak the forces, which may damage the bowsing line and/or the liferaft.